I have a client of mine who is asking about checking/rating of how secure his firewall is. I need something to scan his firewall. I was thinking of GRC, however they only do limited scans. I was also thinking of "nmap" a linux command, however I have to see if I have nmap installed on my system, I know my brother has access to it on his work server. Anything else, maybe some professional place that rates security? Edit: PM me anything that you dont want to post here.